Add manual scan trigger before camera initialization

[nih8]

Problem

The current /qr page embeds the camera scanner directly alongside the other search UI elements. On mobile devices, this can make the scanning experience feel cramped and less focused compared to the other flows on the page.

Proposed solution

Instead of embedding the scanner directly inside the /qr page, add a separate “Scan barcode” option that opens a dedicated full-screen scanner page.

Additional context

The other options on the /qr page, such as searching by product name/barcode and customer support, already open dedicated pages/screens. I thought the barcode scanner could follow a similar navigation flow for better consistency and mobile usability.

🎨 Design & mockups

This is roughly the flow/layout I had in mind:

[nih8]

I'd like to work on this issue. Could I be assigned to it?
@teolemon